key switch troubleshooting

i bought a 78 kz650 and the headlights arent working. it has other electrical issues but i think theyre all related to the key switch. if anyone has a meter handy and can check this for me that would be great. on the back of the key switch theres 2 white (12+) then brown, red, blue, green. when the key is switched in the on position then green and red close. brown and blue appear to be shorted out internally. can someone tell me when/if they have potential out of brown and blue?

According to the wire diagram, when the key is "on" every wire on the switch should have 12v.

ok thanks. i thought it may be bad. i dont have a wire diagram. ok few questions...

i cant find a fuse box on this bike. im thinking the original owner removed it and soldered the 6 wires together and since theres no fuse box it caused the key switch to short out.

there are 6 wires that i think should have been hooked to a fuse.

white - white/red
blue - blue/white
brown/white - red/blue

can someone tell me what colors the wires are on the fuse box? maybe what those wires specifically go to? maybe where i can find a wire diagram?

Post edited by: cannibal440, at: 2007/07/24 11:57

Move the cursor over "KZ information" without clicking. Notice the "filebase" tab on the left appears. Move and click on "filebase". You'll find diagrams to most of the bikes there. Here's a link to 1978 KZ650 B/C diagram in PDF format. There's actually a couple of them there.

78 650 diagram page

Post edited by: loudhvx, at: 2007/07/24 12:16

thanks a bunch!! after studying the diagram for an hour i found my problem! there was a pigtail connection that ties the blue/white, brown, brown/white together. i had potential out of the brown wire but bingo!! nothing out of the blue. i cut the pigtail out and twisted the wires together and everything works now. then i soldered all wires and put heatshrink over the connections. i took all the ratty electrical tape off the wiring harness and used wireloom in its place. someone cut the fuse block out and taped the wires together. i bought 3 water tight fuse holders and added fuses between the blue-blue/white, red-brown/white, white/red-white. after that i secured the wires and put everything back together. now all my electrical problems are solved and everything works. all the instrument lights work minus the blown bulbs. the low side of the headlight is blown but the high works.

Good job!